Inoculum 63(3) - Mycological Society of America

The standard taxonomic treatment of European stipitate hydnoid species
(ectomycorrhizal tooth fungi in the genera Bankera, Hydnellum, Phellodon and
Sarcodon), written by R.A. Maas Geesteranus, is almost 40 years old. It is timely
therefore to re-examine the morphological species concepts therein using the
results of a combined molecular and morphological approach. These fungi have
received conservation-related publicity across Europe and are now generally regarded
as nitrogen-sensitive tree symbionts frequently associating with roots of
Fagaceae and Pinaceae. A decline in European fruiting populations is mainly ascribed
to increased habitat loss and aerial nitrogen deposition. Of the 18 extant
stipitate hydnoid species currently included on the British and Irish checklist, 15
are recognised as of conservation importance (priority BAP species) in the UK.
However all conservation status assessments currently depend on morphological
taxonomic concepts and accurate identification of fruit bodies. Recognising that a
mushroom is a stipitate hydnoid is often straightforward, but naming the species
on existing fruit body criteria can be fraught with difficulty. This is due to a combination
of identification and taxonomic issues. In order to improve assessments
of species distributions, conservation status and ecological/conservation requirements,
we have adopted a combined approach using molecular (ITS1 sequencing)
and traditional (fruit body and spore morphology) methods. We have discovered
that the list of extant taxa is rather longer (and increasing) than the list of currently
accepted names. There are undoubtedly cryptic and not-so-cryptic hydnoid taxa
to be described in Britain and elsewhere in Europe. We are now comparing
species names with sequence-based groupings in order to pin-point the undescribed
species. This combined approach will facilitate stipitate hydnoid identification,
help to locate their “best” sites for conservation and accelerate their belowground
ecological study.
Albu, Sebastian, Tomas A Rush, and M Catherine Aime. Louisiana State University
Agricultural Center, Department of Plant Pathology and Crop Physiology,
Baton Rouge, Louisiana, 70803. Description of two anamorphic yeasts in the
Ustilaginales
Two basidiomycete yeasts belonging to the Ustilaginales were isolated in 2011
from the leaves of several fern species in Baton Rouge, Louisiana. Based on a
combination of assimilation tests and phenotypic characterization, Farysizyma sp.
nov. SA209 (Anthracoideaceae) and Pseudozyma sp. nov. SA575 (Ustilaginaceae)
represent previously undescribed anamorphs in the Ustilaginomycetes.
Colony morphologies are initially yeast-like, subsequently developing pseudohyphal
tufts around the growing margin. Maximum likelihood analyses using four
loci, the internal transcribed spacer (ITS) region, large subunit (LSU) and small
subunit of the nuclear rDNA cistron, and translation elongation factor 1-alpha indicate
that both isolates belong within Ustilaginales. The LSU and ITS regions of
these isolates were compared to sequences of other available Farysizyma and
Pseudozyma anamorphs and to related teleomorphs. Farysizyma sp. nov. SA209
is part of a Farysizyma/Farysia clade in Anthracoideaceae containing all other
known species of Farysizyma. Pseudozyma sp. nov. is sister to Sporisorium
hwangense within a larger clade of predominantly Sporisorium species that includes
the type (S. sorghi). Comparison of our data with phenotypic descriptions
and sequence data from all known species of Farysizyma and Pseudozyma indicates
that neither isolate has been previously described in the anamorphic yeast
state. However, without sequence information from all known members of Ustilaginales,
we cannot rule out the possibility that either of these isolates may represent
a previously described teleomorphic Farysia or Ustilago/Sporisorium
species.
Allen, Michael F. Center for Conservation Biology, University of California,
Riverside, CA 92521 USA. Mycorrhizae and resource acquisition: dynamics
in fluctuating environments
Mycorrhizae exist from organic layers deep into soil profiles, even into fracturing
bedrock. As soils dry, deeper water either from groundwater or from water bound
in cracks and pockets is acquired and utilized or reallocated via hydraulic redistribution.
N is acquired from surface soils even under drought conditions. We utilized
shifts in natural abundance isotope ratios to better understand spatial and
temporal patterns of resource acquisition. Subsequently, utilizing continuous sensor
and observation platforms, we monitored shifts in roots, mycorrhizal fungi,
and respiration in response to changing temperature and moisture. Acute perturbations
consisting of either large storms or drought result in plant mortality, but
also subsequently re-order root and fungal symbiosis shifting both the types and
spatial structure of resource acquisition. This may be because in seasonal environments,
root and fungal activity show complex and often rapid responses to environmental
change. We can utilize these shifts to develop a better understanding
of belowground response dynamics to more chronic climate change or to acute
perturbations such as hurricanes or drought.
Annis, Seanna L 1 , Rafael Garcia 2 , Beth Calder 2 , and Kathryn L Hopkins 3 1 2
.
School of Biology and Ecology, University of Maine, Orono, ME, 04469, Department
of Food Science and Human Nutrition, University of Maine, Orono,
8 Inoculum 63(3), June 2012
ME, 04469, 3 Cooperative Extension, University of Maine, Orono, ME, 04469.
Identification of fungal contamination in bottled maple syrup
Maple syrup processors in the northeastern USA occasionally observe fungal contamination
in their bottled maple syrup containers. The concern is that the contaminants
may pose a health risk. We identified fungal organisms in 32 bottles of
syrup from different processors in the northeastern USA. Most containers had one
fungus, but some were contaminated with multiple fungi. Fungi were identified
by morphology and DNA sequences of their ribosomal internal transcribed spacer
regions and B tubulin genes. Multiple species of the genera Penicillium and Aspergillus,
single species of Wallemia, and as yet unidentified yeasts were isolated
from multiple bottles. Species of Paecolimyces and Cladosporium were isolated
from single bottles of syrup. Some of the genera of Penicillium and Aspergillus
identified are known to produce mycotoxins, and the production of these compounds
in maple syrup is being evaluated. Syrup is typically bottled at 82 C to decrease
the risk of microbial contamination. Spores from some of the fungi were
able to germinate after treatment at 70 C for 3 minutes. A higher bottling temperature
may be one of the changes in bottling practices required to minimize fungal
contamination. This research will result in new recommendations to maple syrup
processors on preventing future fungal contamination of bottled syrup.
Baldrian, Petr, Tomás Vetrovsky, Jana Vorísková, Ivana Eichlerová, Jaroslav
Snajdr, Lucia Zifcáková, and Martina Stursová. Laboratory of Environmental Microbiology,
Institute of Microbiology of the ASCR, Prague, Czech Republic. Exploring
fungal community structure and function in forest soils: challenges
and limitations of current methodologies
Presently, the structure and function of soil fungal communities receives considerable
attention. This attention is fuelled by the recognition of the key role of fungi
in the C and N cycling in soils, especially of the forest biomes. In addition, the recent
establishment of high-throughput-sequencing methods, labelling with stable
isotopes or metaproteomics offers a much higher resolution of the current studies.
The interpretation of experimental results is, however, still challenging due to the
fact that many methods may potentially contain more or less apparent biasses.
This contribution aims to point at the most important limitations of current
methodologies to explore fungal abundance, community composition and function
in forest soils as studied using biomass quantification techniques (PLFA, ergosterol,
qPCR), shotgun or amplicon-based next-generation-sequencing, stable
isotope probing and environmental metaproteomics. In the case of microbial biomass
surveys, our results show that various methods (rDNA quantification, PLFA
or ergosterol assays) yield widely different results of the fungal biomass content
or fungal/bacterial biomass ratio and identify the differences in the composition
of fungal mycelia / genomes as a source of such errors. For the next-generationsequencing
data, we show that shotgun methods are not consistent with PCRbased
methods and that the use of rDNA markers is highly biased due to uneven
content of ITS copies per fungal genome as can be demonstrated if single-copy
genes are sequenced. The approaches to explore the active fraction of the total
fungal community by the analysis of RNA-derived sequencing or the use of Stable
Isotope Probing and, most recently, environmental metaproteomics offer an
attractive insight into the functioning of fungal communities. However, even the
use of these methods must be careful in order to avoid experimental errors.
Barge, Edward G and Cathy L Cripps. Plant Sciences and Plant Pathology Department,
Montana State University, Bozeman, MT 59715. Systematics of Lactarius
in the Rocky Mountain alpine zone
Lactarius is an important ectomycorrhizal genus in the Arctic-Alpine
Biome where it associates primarily with Salix and Betula species. The Arctic-
Alpine Biome covers roughly 8% of the earth’s land and in the Rocky Mountains
of North America the alpine is comprised of scattered “islands” above timberline
in mountainous areas. Beginning in 1999 Cripps, Horak and others surveyed arctic-alpine
macromycete distributions in the Rocky Mountains of Montana, Colorado
and Wyoming. Studies of the ectomycorrhizal fungi present in arctic-alpine
areas are of importance as climate change impacts this biome, which includes the
range expansion of Salix species, a key alpine ectomycorrhizal phytobiont. This
study focuses on the systematics of Lactarius in alpine areas of the Rocky Mountains.
Macromorphological descriptions made at the time of collection, microscopic
examination of dried material and phylogenetic analysis (rough) have contributed
to identification. Drawings of spores, pleuromacrocystidia and
cheilomacrocystidia were completed for each species using a Leica drawing tube
and are complemented with SEM photographs for each species. DNA from upwards
of 48 collections was successfully extracted and the ITS region amplified
using primers ITS1-F and ITS4. Preliminary analysis shows morphologically
identified species grouping together nicely. Thus far, the study has resulted in
identification of six alpine Lactarius species: L. glyciosmus, L. lanceolatus, L.
nanus, L. pseudouvidus, L. repraesentaneus and L. salicis-reticulatae. Other than
a preliminary report, most are first documentations for these species in alpine
Continued on following page